1325856 九、發明說明： 【發明所屬之技術領域】 本發明涉及製備具有高含量4,4’-和2,4·-亞甲基二苯基二異氣 酸酯的在二苯基甲烷系二異氰酸酯類和多異氰酸酯混合物的方 5 法，以及這種混合物用於製備聚合物的應用° 【先前技術】 已知通過使來自二苯基甲烷系的相應二胺和多胺(MDA)光氣 化，可以製備來自二苯基甲烷系的二異氰酸酯和多異氰酸酯 (MDI)。所述來自二苯基甲烷系的相應二胺和多胺本身可以通過 10 縮合苯胺和甲搭來製備。通過使來自一本基甲炫系的一胺類光氣 化，可以製得本領域技術人員稱為雙核MDI(二苯基甲烷系的二 異氰酸酯）的相應二異氰酸酯2,2，-MDI、2,4’-MDI和4,4，_MDI。但 是在縮合苯胺和曱醛時，所述雙核MDA(亞甲基二苯基二胺MDA) 還進一步和甲醛及苯胺反應，製得更多核的MDA級，在光氣化 15 反應之後，使聚合MDI(二苯基甲烷系的多異氰酸酯）中出現多核 物質。對許多實際製備應用而言，較好製得高比例的雙核MDI。 根據目前的已有技術，這可以通過兩種不同的方法實現。 1.在苯胺和甲醛的酸催化縮合反應中使用大大過量的苯 胺，將過量的苯胺從反應混合物中分離，並迴圈。在縮合反應中， 20 大大過量的苯胺製得具有高比例雙核MDA的MDA混合物。反 應中所用苯胺/甲醛比例越高，則反應產物中所含雙核的含量越 高。而且，2,4，-MDA和4,4’-MDA的比例也受酸催化劑濃度的影 響。催化劑濃度高對4,4，-MDA有利。濃度低則對2,4，-MDA有利。 (例如’見EP-158059-B1和EP-3303-B1)。這種MDA級在下文中1325856 IX. Description of the invention: [Technical field to which the invention pertains] The present invention relates to the preparation of a diphenylmethane system II having a high content of 4,4'- and 2,4--methylene diphenyl diisophthalate Method for the mixture of isocyanates and polyisocyanates, and the use of such a mixture for the preparation of polymers. [Prior Art] It is known to phosgenize the corresponding diamines and polyamines (MDA) from the diphenylmethane system. Diisocyanate and polyisocyanate (MDI) from the diphenylmethane system can be prepared. The corresponding diamines and polyamines derived from the diphenylmethane system can be prepared by themselves by condensing aniline and meth. By phosgenating a monoamine from a group of thiophanes, a corresponding diisocyanate 2,2,-MDI, 2 which is known to those skilled in the art as a dinuclear MDI (diphenylmethane diisocyanate) can be obtained. , 4'-MDI and 4, 4, _MDI. However, in the condensation of aniline and furfural, the binuclear MDA (methylene diphenyldiamine MDA) is further reacted with formaldehyde and aniline to obtain a more nuclear MDA grade, after the phosgenation 15 reaction, Polynuclear substances are present in the polymerized MDI (diphenylmethane-based polyisocyanate). For many practical manufacturing applications, a high ratio of dual core MDI is preferred. According to the prior art, this can be achieved in two different ways. 1. A large excess of aniline is used in the acid catalyzed condensation of aniline and formaldehyde to separate excess aniline from the reaction mixture and loop back. In the condensation reaction, a large excess of aniline 20 produces a mixture of MDA having a high proportion of binuclear MDA. The higher the proportion of aniline/formaldehyde used in the reaction, the higher the content of dinuclear acid contained in the reaction product. Moreover, the ratio of 2,4,-MDA and 4,4'-MDA is also affected by the concentration of the acid catalyst. A high catalyst concentration is advantageous for 4,4,-MDA. Low concentrations are good for 2,4,-MDA. (For example 'see EP-158059-B1 and EP-3303-B1). This MDA level is below
25 分別是指用於包含低2,4·-異構體含量或高2,4'-異構體含量的MDI 組合物的聚合物A或聚合物B級。所需MDI組合物可以通過使 預先選擇性製得的MDA級光氣化來製傷。 1325856 2.使用酸催化劑以常規方式由苯胺和甲醛製備聚合mda。 — 所述聚合MDA進行光氣化反應，並通過蒸餾方法分離為富含單 體和富含聚合物的餾分。所述聚合MDI餾分可以用作市售聚合 MDI產品。根據已有技術，所述單體MDI餾分通過蒸顧或結晶 5 分離為異構體4,4’-MDI以及約50% 2,4'-MDI和50。/。4,4，-MDI的 混合物。所述兩種單體的產物可以銷售，或者進一步加工製得具 有高含量雙核MDI以及合適異構體比例的聚合MDI的混合產物。 在兩種情況下’所涉及的投資和能量消耗表明製造具有高比 例雙核MDI的MDI混合物的成本很高。 1〇 在第一種情況下，在苯胺和甲醛縮合反應中，大大過量的苯 · 胺須迴圈使用，通過蒸餾從所述反應混合物中分離並趣圈。 在第二種情況下，除了所需的二胺類以外，苯胺過量較少的 苯胺和曱醛縮合反應製得顯著量的多核MDA級，然後它和二胺 類一起進行光氣化反應。為了從二異氰酸酯和多異氰酸醋（雙枝 15 MDI和多核MDI級)的混合物製得二異氰酸酯，必須將所述二異 氰酸酯從二異氰酸酯和多異氰酸酯的混合物中蒸館出來(單體/聚 合物分離”在將這種單體分離之後’所述異構體必須通過蒸德和 /或結晶相互分離’其中涉及使用大量的設備和高能耗。然後將所 述費力分離的異構體再混合到高單體含量的最终產品中。 ® 20 但是在已有技術的工藝中，通過單體/聚合物分離製得的粗單 體餾份(粗單體，基本上由二異氰酸酯組成)仍舊包含不希望有的 高濃度的次要組分。例如，這種粗MDI單體混合物包含多倍於最 大濃度50ppm的單氯苯和最大20ppm的異氰酸苯酯(較好是聚胺 酯廠商通常所需的最大20ppm單氣苯和最大i〇ppm異氣酸苯 25 醋）。此外’常用粗MDI單體混合物包含顯著量的脲二嗣 (uretdicmeX二聚對-MDI)’當其濃度較高時會導致產品混濁，並導 致MDI中產生固體沉澱。因此在涉及相當多成本和努力的後續蒸 -6- 餾階段中，單體/聚合物分離中蒸館出的二異氰酸醋類必須不含次 要組分。 換句話說，具有具體異構體(2,2’_MDI、2,4，-MDI和4,4，-MDI) 含量的具體MDI級是市售的。因此在已有技術中，對應於次要組 分含量低的市售MDI級的組合物通過借助蒸德和/或結晶的複 雜、多步異構體分離來製造。然後’通過摻合這些MDI級來製備 具體應用所需的異氰酸酯組合物。 但是，對MDI級的許多應用來說，聚合物製造並不需要很高 的4,4，-MDI純度，換句話說，例如在要摻合原料中不要求2,2'-MDI 含量很低。因此從能耗的角度來看’使用通過幾步複雜的蒸餾階 段製得2,2，-MDI含量很低的純4,4'-MDI級，與其他MDI級混合 來製得適於具體應用的異氰酸酯組合物並不能令人滿意。 以下所述也可從已有技術中獲知： 例如，以下兩個文獻說明了借助選擇性MDA合成方法直接 製得混合MDI產物的方法。Keggenhoff，Maehlmann & Eifler(EP-158059Bl)製得4,4'-MDA含量高的MDA混合物，包含 約80% 4,4’-MDA和約10% 2,4，-MDA，且雙核含量約為90% »相 反，Eifler&Ellendt(EP-3303Bl)能製得雙核含量為88%的單體含 量高的 MDA，包含 19% 2,2，-MDA、36% 2,4，-MDA 和 45% 4,4’-MDA»要求苯胺/甲醛的摩爾比大於8，以製備這些產物，這 意味著大量的苯胺必須迴圈。此外，對這些品級中的許多來說， 高消耗的鹽酸(催化劑）和NaOH(中和催化劑）是必需的。尤其 4,4'-MDA含量高的產物表明具體鹽酸催化劑消耗很高。特別是製 備2,4’-MDI含量高且富含單體的MDA級往往會產生高的，常常 是不希望有的次要組分2,2，_臟。在許乡應用巾，由於其反應活 性低’高濃度的2,2，-MDI是不良的。 在文獻中通常已知聚合和單體MDI產品的製備方法。雙核含 量為 46-65°/。的聚合 MDa 可以按照 DE-2750975A1 或 DE-2517301 A1所述方法製備。在所述文獻中詳細說明了主要用於工業分離 MDI單體中異構體的蒸餾(DE-3145010AI)和結晶(EP-A-482490) 兩種方法。但是，沒有一個文獻說明了直接使用來自單體/聚合物 分離工藝的粗單體MDI餾份作為MDI摻合的原料來源。而是本 領域的技術人員致力於最經濟的製備方法，以製備包含98%以上 4,4'_MDI的超純化單體異構體混合物，以及2,4，-MDI和4,4，_MDI 各自均約為50%的混合物，它們可以任選地包含最高25%的 2,2’-MDI(M.stepanski，RFaessler : “New hydrid process for purification and separation of MDI isomers5,Sulzer Chemtech,Presentation at the Polyurethanes Conference 2002 in Salt Lake City, 10/2002)。 在聚胺酯工業中，通過摻合聚合MDI產物和重複蒸顧的單體 產物來製備單體含量高的MDI混合物是一種普通的方法。例如在 US-A-5,258,417中’這種方法就用於製備粘度低的摻合MDI產物。 在許多文獻中已經原則上研究過粗的聚合MDI混合物的純 化方法。例如’試圖使用化學添加劑來除去雜質 (US-A-3,925,437、US-A-3,793,362、DE-A-2316028)。在 DD-A-118，105和GB-A-1，114,690中，加入溶劑以試圖除去化學 鍵合的雜質。DD-A-271，820提到使MDI和TDI(甲苯二異氰酸酯） 解吸’运會導致G.1-1G重量％的原料顯著分解，但是，基本上達 到了除去很難對的化學鍵合的雜質的目的。 USA 3,857,871么開了用於聚合mdi的解吸(stripping)方 法，逆會導致產物中酸度和可水解氣降低。說明 了純化聚合MDI的方法’它顯然也會顯著降低可水解氣的量。但 是’所述產物仍舊包含0.1%的溶劑。 【發明内容】 因此，本發明的目的是提供一種_ 物的簡單料料’錢供製備含量㈣臟混合 混合物的枝，所祕合純含細祕體_的腦 劑、展着舱— σ 一 < 民比例的次要組分，尤其是溶 劑吳氰酸本S旨、脲二綱和光氣。 通過在單獨蒸餾步驟中從粗二 φ,ν^φ . ^ _ 共氟酸酯和多異氰酸酯混合物 中刀離出包含至少95重量%雙核亞甲基二苯 氰酸苯酯最大為20ppm的餾分可以 曰 其-贫Α β 耳現廷一目的，上述雙核亞甲 基一本基二異氰酸酯包含6〇重量 〇/0 ,, Λ/ίτχτ 罝 /g从上 M’-MDI、4·35 重量 /o2,4-MDl 和 0.1-10 重量。 10 【圖式簡單說明】 15 β。圖1 ^些製備臟摻合物的市售原料中雙核含量的示意 圖2是-些摻合MDI產物中雙核含量的示意圖。 【實施方式】 本發明涉及包含至少95重量％雙核亞甲基二苯基二異氰酸醋 的二苯基甲烷系二異氰酸酯餾分的製備方法，其中， 20 a) 在酸催化劑存在下使苯胺和甲駿反應製得包含雙核亞γ φ 基二苯基二胺的二苯基甲烷系二胺和多胺， b) 任選地在溶劑存在下，使該包含雙核亞甲基二苯基二胺的 二苯基甲烷系的二胺和多胺光氣化，製得粗二異氰酸酯和多異氰 酸酯， c) 在帶有低沸點組分的任選上游和/或下游分離的單獨蒸顧 步驟中’從該粗二異氰酸酯和多異氰酸酯中分離包含至少95重 量％雙核亞甲基二苯基二異氰酸酯、最大20ppm的異氰酸苯酯以 及任選地最大50ppm的溶劑的餾分；以所述雙核亞曱基二苯基二 25 異氰酸醋餾分的質量計，所述餾分具有60重量。以上的 4,4’-Ινωΐ、4·35 重量％的 2,4，-MDI 以及 0.01-10 重量％的 2,2，-MDl。 在步驟此C)中，包含至少99重量％雙核亞甲基二苯基二異氛 酸醋和最大l〇ppm的異氰酸苯酯以及任選的最大2〇ppm的溶劑 的館分較好從所述粗二異氰酸酯和多異氰酸酯中分離出來；以所 述館分的質量計，上述雙核亞甲基二苯基二異氰酸酯具有76重 量％以上的4,4，-MDI、5-22重量％的2,4，-MDI以及0.2-3重量％的 2,2'-MD 卜 所述異氰酸苯酯和溶劑的最大濃度是以分離的整個餾分質量 計算的。 在單獨蒸餾步驟中分離所述餾分是指，在所述單獨蒸餘步驟 中僅使所述分離的MDI完全蒸發，並再次冷凝，在蒸餾柱的另一 部分作為餾分獲得。相反，在低沸點組分的任選上游和/或下游分 離中’通過蒸發和隨後的冷凝分離主要低沸點的組分。大多數 MDI在分離所述低沸點組分時不會蒸發。 因此’在單獨蒸餾步驟中分離所述餾分還意味著尤其在本發 明的工藝中’在單獨蒸餾步驟中從粗二異氰酸酯和多異氰酸酯中 分離所述餾分之後，基本上不會再分離所述異構化的MDI二異氰 酸醋。 通過本發明的方法，可以製得以所述餾分的質量計高雙核 MDI含量至少為95重量％且次要組分比例低的高單體含量mdi 混合物’其能耗明顯比已有技術的分離方法低。相比已有技術的 方法’此處能耗降低是由於避免了苯胺和甲醛縮合反應使用大大 過量的苯胺、該苯胺後續蒸餾和迴圈。但是同時，通過本發明的 方法’在蒸餾光氣化反應所得二異氰酸酯和多異氰酸酯混合物 中’僅一步蒸餾降低不需要的次要組分的量，並不需要後續的蒸 館步驟。在本發明的方法中避免通過多步蒸餾來分離異構體，同 1325856 時除去不需要的次要組分(按照已有技術）。 在已有技術的MDI異構體蒸館中，還需要相當的技術努力來 破壞痕量組分如可水解的氯組分。但是’這種痕量組分並不是高 單體含量Mm混合物中的有害物質^ 了除去所述殘留的痕量组 5 分，在其以、純4,4，·ΜΙ)Ι銷售之前，在異構職館過程中，單體 麵通常要蒸發和冷卻約4-6 :欠。相反，由於疆在帶有低沸點 組分的任選上游和/或下游分離的單獨蒸够射製得，本發明製 備溶劑含量低的粗單體MDI的能耗低得多。 通過在單體/聚合物分離階段除去麻須的低海點次要組分如 〇 異氰酸苯酯和任選的溶劑，本發明所述方法可以製得至少95重 量％(以所雜分質量計）的高雙核MDI含量的高單體含量眶 館分。步驟〇中，單獨f步驟的分離較好在卜5〇毫巴的絕對壓 力（蒸餾柱頂部）和100-30(rc溫度下進行。在製備所述包含至少 95重量錢核亞甲基二苯基二異氰酸§旨和最大異氰酸笨醋 5 和任選最大50PPm溶劑的餾分過程中除去所述次要組分可以通 過在蒸餾(單體/聚合物分離）中解吸所述粗MDI單體混合物或者 通過在實際單體/聚合物分離之前除去所述低滞點組分來進行。 解吸在蒸館(單體/聚合物分離)過程中所得粗MDI單體混合 物涉及用一小股分流MDI異構體在解吸柱頂部分離出所述包含 ° 溶劑、異氰酸苯酯和例如少量殘留光氣的低沸點組分。所述分離 的低沸點館分可以返回所述MDI/溶劑練階段，或者較好送到單 獨的低沸點組分分離柱，使之不含溶劑和異氰酸苯酯，並且作為 額外MDI原料迴圈或者單獨使用。 若省去通過解吸分離低沸點組分’所述單體/聚合物分離階段 5 可以设计為是帶有排出側流(side stream)的蒸餾枉。此處，所述乾 淨的MDI單體混合物可以以所述蒸餾柱的侧流分離，低沸點組分 則在所述蒸餾柱的頂部分離。所述低沸點組分可以迴圈，或者較 好在單獨的低彿點組分分離枉中使之不含溶劑和異氰酸苯醋。 也可以改進所述低沸點組分的除去方法，這樣實際上不將異 氰酸苯S旨聽騎料體/聚合物雜階段。例如，這可以通過在 單體/聚合物分離步驟前將來自任選多步溶劑除k藝的館出物 返回到所述第一溶劑分離階段來實現。 結晶也是一種適於純化粗MDI單體混合物的方法。 在這一方法中，通過單體/聚合物分離步驟由蒸餾柱製得的產 物較好迅速驟冷至35_8(rc，以降低腺二酮的含量。合適的連續 MDI單體流的驟冷方法在已有技術巾已經存在。例如，帶有迴圈 泵和例如60C熱交換器的循環系統適於在最短時間内將所述熱 產物從約14〇-2〇〇。〇冷卻至6(rc，由此使脲二酮生成最小。 本發明還涉及從二苯基曱烷系製備含有二異氰酸酯的混合物 的方法，其中： a) 通過上述工藝製備包含至少95重量％雙核亞甲基二苯基 二異氣酸醋和最大2〇ppm異氰酸苯酯和任選最大50ppm溶劑的 德分’相對於該餾分質量計，上述雙核亞甲基二苯基二異氰酸酯 具有60重量％以上的44LMDI、4 35重量％的2,4，_MDI以及 0.01-10 重量％的 2,2，-MDI， b) 將步驟a)中製得的餾分和一種或多種包含二苯基甲烷系 二異氰酸酯和/或多異氰酸酯的混合物摻合。 本發明方法製得的包含至少95重量％雙核MDI的二苯基甲 烷系二異氰酸酯餾分可以用於和多核（聚合)MDI及市售MDI級掺 合，製得雙核MDI和多核MDI比例可自由調節以及各種MDI異 構體比例可自由調節的任何MDI混合物。 通過本發明方法製得的二苯基甲烷系二異氰酸酯餾分具有優 選的如下組成： •總雙核含量：295重量％ ; 1325856 • 4,4’-MDI含量：>60重量％，以餾分總量計； • 2,4'-MDI含量：4-35重量％，以餾分總量計； • 2,2'-MDI含量：0.01-10重量％，以餾分總量計； •溶劑含量：0-50ppm，以餾分總量計； 5 •異氰酸苯酯含量：0-20ppm，以餾分總量計； •脲二酮含量：0-0.5重量°/❶，以餾分總量計。 尤其優選的餾分組成如下： •總雙核含量：299重量％ ; • 4,4'-MDI含量：>76重量％，以餾分總量計； 10 ·2,4'-ΜϋΙ含量：5-22重量％，以餾分總量計； • 2,2'-MDI含量：0.2-3重量％，以餾分總量計； •溶劑含量：0-20ppm，以德分總量計； •異氰酸苯酯含量：〇-l〇ppm，以餾分總量計； •脲二酮含量：0-0.1重量％，以餾分總量計。 15 本發明方法製得的包含至少95重量％雙核MDI的二苯基甲 烷系二異氰酸酯餾分可以和多異氰酸酯或其他有機異氰酸酯摻 合。圖1提供了製備MDI摻合物的市售原料產品的示意圖。圖2 顯示在相同參數範圍中MDI系摻合產物的一些實例。所述橫轴表 示雙核總含量，縱軸表示鄰位-雙核總含量（2,2'-MDI + 20 2,4’-MDI)。所述虛線形成三角形，在該三角形中，由具體的原料 產品可以製備摻合物。 本發明方法製得的包含至少95重量％雙核MDI的二苯基甲 烷系二異氰酸酯餾分可以和一種或多種包含芳族異氰酸酯的混 合物摻合。除了較好使用上述包含二苯基甲烷系二異氰酸酯和/ 25 或多異氰酸酯的混合物以外，還較好使用包含甲苯二異氰酸酯類 (例如，2,4-TDI、2,6-TDI)或者包含萘二異氰酸酯類(例如，1，5-NDI) 的混合物或者這些異氰酸酯的混合物。但是原則上，也可以使用 •13- 其他芳族和/或脂族單·、二-、三-或多官能異氰酸酯類進行摻合。 本發明方法製得的包含至少95重量％雙核MDI的二苯基甲 燒系二異氰酸醋德分以及由它們製備的摻合產物可以用於常規 的異氰酸酯改性反應，如碳二亞胺化以及合成uret〇nimine，或者 用於内0H-官能聚酯，C2、C3和/或〇4聚醚、脲二酮、腺基甲酸 S曰、縮二腺和/或腺衍生物製備預聚物。 本發明方法製得的包含至少95重量。/〇雙核MDI的二苯基甲 烷系二異氰酸酯餾分可以作為混合組分與其他MDI系二異氰酸 酯和多異氰酸酯混合’和/或與用於製備異氰酸酯組分的其他異氰 酸酯混合，用於製備聚合物。由這些摻合產物製得的最終部分覆 蓋了整個聚胺酯化學領域。舉例說明如下： •用於絕緣和致冷工業的硬質泡沫材料 •包裝泡沫材料 •用於傢俱和車輛工業的軟質泡沫材料和軟質模塑泡沫材料 •塗料、粘合劑、密封劑和彈性體應用 •半硬質聚胺酯泡沫材料 本發明可以製備摻合MDI產品，當在MDI異構體分離階段 進行蒸餾或在MDA階段進行苯胺蒸餾時’使用的設備少得多， 且能耗降低。同時，若可以避免使用聚合物A或聚合物B級(在 已有技術中使用大量鹽酸(控制MDA中異構體分佈)和Na〇H來 製備的）的話，在MDA階段中平均鹽酸和Na〇H原料消耗會顯著 降低。 在許多摻合產物中，若不再直接製備2,2，_MDI含量高的聚合 物B級並用作單體含量高的最終產品用混合組分，也可以降^ 2,2’-MDI的含量。在摻合物中使用2 2，-MDI含量低的，如本 發明方法所得的2,2，_MDI含量低的餾分，可以通過摻合來製備 2J-MDI含量明顯更低且反應活性提高的厘汉產物。由它們製得 的聚合物也呈現出改進的聚合物性質。 實施例 參考以下實施例綱了解決本㈣目_方法。所有％值均 以重量％(Wt%)計。 可以使用以下所述組成的MDI原料來製備市售臟混合物 (MCB=單氯苯溶劑，PHI=異氰酸苯酯” 級別 2,2，-MDI 2,4，-MDI 4,4'-MDI 雙核總量 MCB PHI 聚合物級 (200mPas) <0.2% 3% 39% 42% <10ppm <8ppm 純4,4’-級 0% 1.5% 98.5% ^00% <10ppm <8ppm 富2,4’-級 <2% 55% 44% J00% <10ppm <8ppm 富2,2’-級 50% 50% 0% 100% <10ppm ^δρριη 聚合物A級 0.7% 11% 78% 90% -------( <10ppm <8ppm 聚合物B級 6% 31% 51% 88% <10ppm <8ppm 粗單體 0.7% 11% 88% >99% 250ppm 44ppm 純的粗單衝 0.7% 11% 88% ^9.5% 15ppm 8ppm *由本發明方法製得的餾分 10 使用命過量的苯胺製備兩種聚合物級A和b，因此需要對笨 胺進行複雜和昂貴的蒸德和迴圈使用。另—方面，所述MDI異構 體蒸餾產物純4,4'-、富2,4’-和富2,2’-級可以如下所述製備：對光 氣化反應製得的二異氰酸酯和多異氰酸酯混合物進行極其複雜 15 的多步蒸餾，以分離出所述不需要的次要組分，並建立所需的各 雙核 MDI 異構體(2,4，-MDI、2,2，-MDI 和 4,4，_MDI)的規格。 另一方面，通過單獨的蒸餾可以不費力且低能耗地從光氣化 反應製得的二異氰酸酯和多異氰酸酯混合物製得聚合物級和粗 -15- 粗單體和純的粗單體）。此處，所錢合物_為底部產 並且匕包含向比例的多核MDI。所述粗單體級在蒸餾柱 頂。作為触排it}。粗單鮮賴粗單體*同之處在於所述純 的粗單體時由本發日月所述方法製得，因此僅有很傾留比例的次 要組分’如異氰酸苯S旨和任選的溶劑，因此，不需要額外的蒸館 加工。 實施例1(對比） 由17重量％聚合物級、51重量％聚合物級A和32重量％聚 合物級B製得的混合河01產物具有以下產品質量(MCB==作為溶 劑的單氣苯）： 級別 2,2，-MDI 2,4'-MDI 4,4'-MDI 雙核MDI總量 MCB 摻合物1 3.9% 16.3% 62.5% 82.7% <10ppm 雖然不能使用精顧的產物(純4,4’-級、富2,2，-級、富2,4，·級) 來製備摻合物1，但是必須使用83重量❶/。聚合物A級和/或B(使 用很複雜的方法製得）》因此，實施例1中製備摻合物丨很耗能。 實施例2(對比） 由36.4重量％聚合物級、37.1% 4,4，-級和26.5% 2,4，-級製得 的混合MDI產物具有以下產品質量： 級別 2,2'-MDI 2,4'-MDI 4,4，-MDl 雙核MDI總量 MCB 摻合物2 0.3% 16.3% 62.5% 79.1% <10ppm25 refers to polymer A or polymer B grade, respectively, for an MDI composition comprising a low 2,4·-isomer content or a high 2,4'-isomer content. The desired MDI composition can be made by gasifying the previously selectively produced MDA grade phosgen. 1325856 2. Preparation of polymeric mda from aniline and formaldehyde in a conventional manner using an acid catalyst. - The polymerized MDA is subjected to a phosgenation reaction and separated into a monomer-rich and polymer-rich fraction by distillation. The polymeric MDI fraction can be used as a commercially available polymeric MDI product. According to the prior art, the monomeric MDI fraction is separated into the isomer 4,4'-MDI and about 50% 2,4'-MDI and 50 by distillation or crystallization 5 . /. a mixture of 4,4,-MDI. The products of the two monomers can be sold or further processed to produce a mixed product of polymeric MDI having a high content of dinuclear MDI and a suitable isomer ratio. The investment and energy consumption involved in both cases indicates that the cost of manufacturing an MDI mixture with a high ratio of dual core MDI is high. 1〇 In the first case, in the condensation reaction of aniline and formaldehyde, a large excess of benzeneamine is used in a loop, separated from the reaction mixture by distillation and fun. In the second case, in addition to the desired diamines, the aniline and furfural condensation reaction with a small excess of aniline produces a significant amount of polynuclear MDA grade, which is then subjected to a phosgenation reaction with the diamines. In order to obtain a diisocyanate from a mixture of a diisocyanate and a polyisocyanate (double branch 15 MDI and a polynuclear MDI grade), the diisocyanate must be evaporated from a mixture of diisocyanate and polyisocyanate (monomer/polymerization) Separation "after separation of such monomers, the isomers must be separated from one another by steaming and/or crystallization" which involves the use of large amounts of equipment and high energy consumption. The laboriously separated isomers are then remixed. In the final product with high monomer content. ® 20 However, in the prior art process, the crude monomer fraction (rough monomer, consisting essentially of diisocyanate) obtained by monomer/polymer separation still contains Undesirably high concentration of minor components. For example, such a crude MDI monomer mixture contains multiples of monochlorobenzene at a maximum concentration of 50 ppm and phenyl isocyanate up to 20 ppm (preferably a polyurethane manufacturer usually requires The maximum 20ppm single gas benzene and the maximum i〇ppm isogas benzene 25 vinegar). In addition, the 'common crude MDI monomer mixture contains a significant amount of urea dioxime (uretdicmeX dimerization pair - MDI)' when its concentration is high Lead to production The product is turbid and leads to solid precipitation in the MDI. Therefore, in the subsequent steaming -6-distillation stage involving considerable cost and effort, the diisocyanate in the monomer/polymer separation must be free of secondary In other words, specific MDI grades with specific isomers (2,2'-MDI, 2,4,-MDI and 4,4,-MDI) are commercially available. A commercially available MDI grade composition corresponding to a low level of secondary components is produced by separation of complex, multi-step isomers by steaming and/or crystallization. Then, by blending these MDI grades, a specific application is prepared. The desired isocyanate composition. However, for many applications of the MDI grade, polymer manufacturing does not require high 4,4,-MDI purity, in other words, 2, 2 is not required, for example, in the blending of the raw materials. '-MDI content is very low. Therefore, from the point of view of energy consumption, 'the pure 4,4'-MDI grade with very low 2,2,-MDI content obtained through several complicated distillation stages is mixed with other MDI grades. It is not satisfactory to prepare an isocyanate composition suitable for a specific application. The following description is also known from the prior art. : For example, the following two documents describe the direct preparation of mixed MDI products by means of selective MDA synthesis. Keggenhoff, Maehlmann & Eifler (EP-158059Bl) produces MDA mixtures with high 4,4'-MDA content, including About 80% 4,4'-MDA and about 10% 2,4,-MDA, and the dinuclear content is about 90% »In contrast, Eifler & Ellendt (EP-3303Bl) can produce a monomer content of 88% binuclear content. High MDA, containing 19% 2,2,-MDA, 36% 2,4,-MDA and 45% 4,4'-MDA» requires an aniline/formaldehyde molar ratio greater than 8, to prepare these products, which means A large amount of aniline must be looped. In addition, for many of these grades, high consumption of hydrochloric acid (catalyst) and NaOH (neutralization catalyst) are necessary. In particular, products with a high 4,4'-MDA content indicate that the specific hydrochloric acid catalyst is expensive. In particular, the preparation of 2,4'-MDI high and monomer-rich MDA grades tends to produce high, often undesirable, minor components 2,2,_dirt. In the application of towels in Xuxiang, due to its low reactivity, high concentrations of 2,2,-MDI are undesirable. The preparation of polymeric and monomeric MDI products is generally known in the literature. The binuclear content is 46-65°/. The polymeric MDa can be prepared as described in DE-2750975A1 or DE-2517301 A1. Distillation (DE-3145010AI) and crystallization (EP-A-482490), which are mainly used for industrial separation of isomers in MDI monomers, are described in detail in the literature. However, none of the literature teaches the direct use of the crude monomer MDI fraction from the monomer/polymer separation process as a source of raw material for MDI blending. Rather, those skilled in the art are dedicated to the most economical preparation process to prepare a mixture of ultrapure monomer isomers comprising more than 98% 4,4'-MDI, and 2,4,-MDI and 4,4,_MDI, respectively. Approximately 50% of the mixture, which may optionally contain up to 25% of 2,2'-MDI (M. stepanski, RFaessler: "New hydrid process for purification and separation of MDI isomers 5, Sulzer Chemtech, Presentation at the Polyurethanes Conference 2002 in Salt Lake City, 10/2002). In the polyurethane industry, it is a common method to prepare a mixture of MDIs with high monomer content by blending the polymerized MDI product with the re-distilled monomer product. For example, in US- A-5, 258, 417 'This method is used to prepare blended MDI products with low viscosity. The purification of crude polymeric MDI mixtures has been studied in principle in many literatures. For example 'Trying to use chemical additives to remove impurities (US- A-3, 925, 437, US-A-3, 793, 362, DE-A-2316028). In DD-A-118, 105 and GB-A-1, 114, 690, a solvent is added in an attempt to remove chemically bonded impurities. DD-A-271 , 820 mentions making MDI and TDI ( The desorption of benzene diisocyanate results in a significant decomposition of the G.1-1G wt% of the starting material, but essentially achieves the goal of removing chemically bonded impurities that are difficult to correct. USA 3,857,871 desorbs the polymerized mdi ( The stripping method, which results in a decrease in acidity and hydrolyzable gas in the product, illustrates the method of purifying the polymerized MDI 'it obviously also significantly reduces the amount of hydrolyzable gas. But the product still contains 0.1% solvent. Therefore, the object of the present invention is to provide a simple material of a kind of material for the preparation of the content of the (four) dirty mixed mixture, the secret of the pure brain containing secret agent _, the exhibition cabin - σ a < The secondary component of the proportion, especially the solvent sulphate, S. urethane and phosgene. From the crude φ, ν^φ . ^ _ eufluoride and polyisocyanate mixture in a separate distillation step The cleavage of a fraction containing at least 95% by weight of phenyl dinuclear methylene diphenyl cyanate of up to 20 ppm can be used for the purpose of the present invention. The above-mentioned dinuclear methylene-based diisocyanate contains 6 〇 by weight. 〇/0 ,, / Ίτχτ catching rabbits / g from M'-MDI, 4 · 35 wt / o2,4-MDl and 0.1 to 10 wt. 10 [Simple description of the diagram] 15 β. Figure 1 is a schematic representation of the dinuclear content of some commercially available feedstocks for the preparation of dirty blends. Figure 2 is a graphical representation of the dinuclear content of some blended MDI products. [Embodiment] The present invention relates to a process for producing a diphenylmethane-based diisocyanate fraction comprising at least 95% by weight of dinuclear methylene diphenyl diisocyanate, wherein 20 a) an aniline and an anion in the presence of an acid catalyst The reaction of the reaction produces a diphenylmethane-based diamine and a polyamine comprising a dinuclear sub-gamma φ-diphenyldiamine, b) optionally comprising a dinuclear methylene diphenyldiamine in the presence of a solvent The diphenylmethane-based diamine and polyamine are phosgenated to produce crude diisocyanate and polyisocyanate, c) in a separate steaming step with optional upstream and/or downstream separation of low boiling components. Separating a fraction comprising at least 95% by weight of dinuclear methylene diphenyl diisocyanate, up to 20 ppm of phenyl isocyanate and optionally up to 50 ppm of solvent from the crude diisocyanate and polyisocyanate; The fraction has a weight of 60 parts by weight based on the mass of the diphenyldi25 isocyanate fraction. The above 4,4'-Ινωΐ, 4.35 wt% of 2,4,-MDI and 0.01-10 wt% of 2,2,-MDl. In the step C), the inclusion of at least 99% by weight of dinuclear methylene diphenyl diiso-succinic acid vinegar and a maximum of 1 〇 ppm of phenyl isocyanate and optionally a solvent of up to 2 〇 ppm is preferred. Separating from the crude diisocyanate and the polyisocyanate; the dinuclear methylene diphenyl diisocyanate has 76% by weight or more of 4,4,-MDI, 5-22% by weight based on the mass of the mass fraction The maximum concentration of 2,4,-MDI and 0.2-3 wt% of 2,2'-MD of the phenyl isocyanate and solvent is calculated as the mass of the entire fraction separated. Separating the fraction in a separate distillation step means that only the separated MDI is completely evaporated in the separate distillation step and is again condensed, and is obtained as a fraction in another portion of the distillation column. Instead, the predominantly low boiling component is separated by evaporation and subsequent condensation in the optional upstream and/or downstream separation of the low boiling component. Most MDI does not evaporate upon separation of the low boiling components. Thus 'separating the fractions in a separate distillation step also means that, in particular in the process of the invention, after separating the fractions from the crude diisocyanate and the polyisocyanate in a separate distillation step, the separation is not substantially separated again. Constructed MDI diisocyanate. By the method of the invention, it is possible to produce a high monomer content mdi mixture having a high dinuclear MDI content of at least 95% by weight and a low proportion of secondary components of the fraction, which is significantly more energy-consuming than prior art separation methods. low. The lower energy consumption here compared to the prior art method is due to the avoidance of the aniline and formaldehyde condensation reaction using a large excess of aniline, subsequent distillation and looping of the aniline. At the same time, however, the amount of unwanted minor components is reduced by the one-step distillation of the diisocyanate and polyisocyanate mixture obtained by the phosgenation reaction in the process of the present invention, and no subsequent steaming step is required. The separation of the isomers by multi-step distillation is avoided in the process of the invention, and the unwanted minor components are removed as in 1325856 (according to the prior art). In prior art MDI isomer vaporizers, considerable technical effort is required to destroy trace components such as hydrolyzable chlorine components. However, 'this trace component is not a harmful substance in the mixture of high monomer content Mm ^ removes the residual trace amount of 5 points, before it is sold in pure 4,4,·ΜΙ) During the heterogeneous job hall, the monomer face usually evaporates and cools about 4-6: owe. In contrast, the crude monomer MDI having a low solvent content of the present invention has a much lower energy consumption due to the separate vaporization of the upstream and/or downstream separation with low boiling components. The process of the present invention can produce at least 95% by weight by removing the low sea point secondary component of the whisker, such as phenyl isocyanate and optionally the solvent, during the monomer/polymer separation stage. The high monomer content of the high dual-core MDI content of the mass meter). In the step 〇, the separation of the separate f steps is preferably carried out at an absolute pressure of 5 mbar (top of the distillation column) and at a temperature of 100-30 (rc temperature). The preparation comprises at least 95% by weight of methylene methylene diphenyl. Removal of the secondary component during the distillate of the diisocyanate and the maximum isocyanate 5 and optionally the maximum of 50 ppm of solvent can be achieved by desorbing the crude MDI in distillation (monomer/polymer separation) The monomer mixture is either carried out by removing the low hysteresis component prior to the actual monomer/polymer separation. Desorption of the crude MDI monomer mixture obtained during the steaming (monomer/polymer separation) involves the use of a small fraction The split MDI isomer separates the low boiling component comprising the solvent, phenyl isocyanate and, for example, a small amount of residual phosgene at the top of the desorption column. The separated low boiling point fraction can be returned to the MDI/solvent In the stage, it is better to send to a separate low-boiling component separation column to be free of solvent and phenyl isocyanate, and to be used as an additional MDI feedstock or separately. If the removal of low-boiling components by desorption is omitted. The monomer/polymer separation stage 5 can be designed to be a distillation enthalpy with a side stream. Here, the clean MDI monomer mixture can be separated by a side stream of the distillation column, and the low boiling component is at the distillation column. Separating the top portion. The low-boiling component may be looped, or preferably separated from the solvent of the low-point component, and the isocyanate-free benzene vinegar. The removal method is such that the isocyanate benzene is not actually intended to listen to the riding body/polymer phase. For example, this can be done by removing the optional multi-step solvent before the monomer/polymer separation step. The product is returned to the first solvent separation stage. Crystallization is also a method suitable for purifying a crude MDI monomer mixture. In this method, the product obtained from the distillation column by the monomer/polymer separation step is more Quickly rapidly quench to 35_8 (rc to reduce the content of glandodione. The quenching method of a suitable continuous MDI monomer stream is already present in prior art towels. For example, with a loop pump and a 60C heat exchanger, for example The circulation system is adapted to be said in the shortest time The product is cooled from about 14 〇 to 2 〇〇. 〇 is cooled to 6 (rc, thereby minimizing uretdione formation. The invention also relates to a process for preparing a mixture containing diisocyanate from a diphenyl decane series, wherein: a) Preparing a dicore comprising at least 95% by weight of dinuclear methylene diphenyl diisoxamic acid vinegar and up to 2 ppm by weight of phenyl isocyanate and optionally up to 50 ppm solvent by the above process, relative to the fraction mass Methylene diphenyl diisocyanate has 60% by weight or more of 44LMDI, 435 % by weight of 2,4,_MDI and 0.01 to 10% by weight of 2,2,-MDI, b) obtained in the step a) The fraction is blended with one or more mixtures comprising diphenylmethane diisocyanate and/or polyisocyanate. The diphenylmethane diisocyanate fraction comprising at least 95% by weight of dinuclear MDI prepared by the process of the invention can be used for blending with multi-core (polymeric) MDI and commercially available MDI grades, and the ratio of dual-core MDI and multi-core MDI can be adjusted freely. And any MDI mixture with a freely adjustable ratio of MDI isomers. The diphenylmethane-based diisocyanate fraction obtained by the process of the invention has the following preferred composition: • Total binuclear content: 295 wt%; 1325856 • 4,4'-MDI content: > 60 wt%, based on the total fraction • 2,4'-MDI content: 4-35 wt%, based on the total fraction; • 2,2'-MDI content: 0.01-10% by weight, based on the total fraction; • Solvent content: 0- 50 ppm, based on the total amount of the fraction; 5 • phenyl isocyanate content: 0-20 ppm, based on the total amount of the fraction; • uretdione content: 0-0.5 weight °/❶, based on the total amount of the fraction. Particularly preferred fractions are as follows: • Total binuclear content: 299% by weight; • 4,4'-MDI content: > 76% by weight, based on the total fraction; 10 · 2,4'-ΜϋΙ content: 5-22 % by weight, based on the total amount of the fraction; • 2,2'-MDI content: 0.2-3% by weight, based on the total amount of the fraction; • Solvent content: 0-20 ppm, based on the total amount of the deuterium; • Benzene isocyanate Ester content: 〇-l〇ppm, based on the total amount of the fraction; • Ureadione content: 0-0.1% by weight, based on the total amount of the fraction. 15 The diphenylmethane diisocyanate fraction comprising at least 95% by weight of dinuclear MDI produced by the process of the invention may be blended with a polyisocyanate or other organic isocyanate. Figure 1 provides a schematic of a commercially available starting product for the preparation of an MDI blend. Figure 2 shows some examples of MDI-based blended products in the same parameter range. The horizontal axis represents the total content of the binuclear and the vertical axis represents the total ortho-dinuclear content (2, 2'-MDI + 20 2, 4'-MDI). The dotted line forms a triangle in which a blend can be prepared from a specific raw material product. The diphenylmethane diisocyanate fraction comprising at least 95% by weight of the binuclear MDI produced by the process of the invention may be blended with one or more mixtures comprising aromatic isocyanates. In addition to preferably using the above mixture comprising diphenylmethane-based diisocyanate and /25 or polyisocyanate, it is preferred to use toluene diisocyanate (for example, 2,4-TDI, 2,6-TDI) or naphthalene. A mixture of diisocyanates (for example, 1,5-NDI) or a mixture of these isocyanates. In principle, however, it is also possible to blend with other aromatic and/or aliphatic mono-, di-, tri- or polyfunctional isocyanates. The diphenylmethane diisocyanate fractions comprising at least 95% by weight of dinuclear MDI prepared by the process of the invention and the blended products prepared therefrom can be used in conventional isocyanate modification reactions such as carbodiimides. And synthetic uret〇nimine, or for the preparation of pre-polymerization of internal 0H-functional polyesters, C2, C3 and/or 〇4 polyethers, uretdione, thioglycolic acid S, dimers and/or gland derivatives Things. The process of the invention produces at least 95 weights. The diphenylmethane diisocyanate fraction of the bismuth dinuclear MDI may be mixed as a mixed component with other MDI-based diisocyanate and polyisocyanate' and/or mixed with other isocyanate used to prepare the isocyanate component for the preparation of a polymer. The final portion made from these blended products covers the entire field of polyurethane chemistry. Examples are as follows: • Rigid foams for the insulation and refrigeration industries • Packaging foams • Flexible foams and soft molded foams for the furniture and vehicle industries • Coatings, adhesives, sealants and elastomer applications • Semi-rigid polyurethane foam The present invention allows for the preparation of blended MDI products which, when distilled in the MDI isomer separation stage or aniline distillation in the MDA stage, are used in much less equipment and have reduced energy consumption. At the same time, if it is possible to avoid the use of polymer A or polymer B grade (prepared in the prior art using a large amount of hydrochloric acid (controlling the distribution of isomers in MDA) and Na〇H), the average hydrochloric acid and Na in the MDA stage. 〇H raw material consumption will be significantly reduced. In many blended products, if the polymer B grade with high 2,2,_MDI content is not directly prepared and used as a mixed component for the final product with high monomer content, the content of 2,2'-MDI can also be reduced. . In the blend, a fraction having a low content of 2 2,-MDI, such as the 2,2,_MDI content obtained by the method of the present invention, can be prepared by blending to prepare a 2J-MDI content which is significantly lower and the reactivity is improved. Han products. The polymers made from them also exhibit improved polymer properties. EXAMPLES The following examples are presented to solve the method of the present invention. All % values are in weight % (Wt%). A commercially available dirty mixture (MCB = monochlorobenzene solvent, PHI = phenyl isocyanate) grade 2, 2, -MDI 2,4,-MDI 4,4'-MDI can be prepared using the MDI starting materials of the composition described below. Dual core total MCB PHI polymer grade (200mPas) <0.2% 3% 39% 42% <10ppm <8ppm pure 4,4'-grade 0% 1.5% 98.5% ^00% <10ppm <8ppm Rich 2,4'-grade <2% 55% 44% J00% <10 ppm <8 ppm Rich 2,2'-grade 50% 50% 0% 100% <10 ppm ^δρριη Polymer Grade A 0.7% 11% 78% 90% -------( <10ppm <8ppm Polymer Grade B 6% 31% 51% 88% <10ppm <8ppm Crude Monomer 0.7% 11% 88% >99% 250ppm 44 ppm pure crude single punch 0.7% 11% 88% ^9.5% 15 ppm 8 ppm * Fraction 10 made by the process of the invention The use of an excess of aniline to prepare two polymer grades A and b, thus requiring complex and expensive stupid amines In addition, the MDI isomer distillation product pure 4,4'-, rich 2,4'- and rich 2,2'-grade can be prepared as follows: phosgene The diisocyanate and polyisocyanate mixture obtained by the reaction is subjected to an extremely complicated 15 multi-step distillation to separate Describe the unwanted minor components and establish the specifications for each of the binuclear MDI isomers (2,4,-MDI, 2,2,-MDI and 4,4,_MDI). Distillation can produce polymer grade and crude -15-crude monomer and pure crude monomer from the mixture of diisocyanate and polyisocyanate prepared by phosgenation reaction without any difficulty and low energy consumption. The material is produced at the bottom and the ruthenium contains a proportional multi-core MDI. The crude monomer stage is at the top of the distillation column. As the banknote it}. The crude single monomer is the same as the pure crude monomer. It is prepared by the method described in the present day, so that only a very small proportion of the secondary component 'such as isocyanate benzene and optional solvent are used, and therefore, no additional steaming process is required. (Comparative) The mixed river 01 product prepared from 17% by weight of polymer grade, 51% by weight of polymer grade A and 32% by weight of polymer grade B had the following product qualities (MCB == monogas as solvent): 2,2,-MDI 2,4'-MDI 4,4'-MDI Dual core MDI total MCB Blend 1 3.9% 16.3% 62.5% 82.7% <10ppm Although not used The product (pure grade 4,4, 2,2 rich, - Class rich 2,4-stage) to prepare a blend, but must use the 83 wt ❶ /. Polymer Grade A and/or B (made using a very complicated process). Therefore, the preparation of the blend of ruthenium in Example 1 is very energy intensive. Example 2 (Comparative) A mixed MDI product prepared from 36.4 wt% polymer grade, 37.1% 4,4,-grade and 26.5% 2,4,-grade had the following product qualities: Grade 2, 2'-MDI 2 , 4'-MDI 4,4,-MDl Dual core MDI total MCB Blend 2 0.3% 16.3% 62.5% 79.1% <10 ppm
雖然製備摻合物2不需要任何精心製備的聚合物MDA級A 1325856 r 或B ’或光氣化產物（聚合物a和b)，但是必須使用64重量❶/〇純 4,4’-和富2,4’-的級(使用很複雜的方法製得）。因此，實施例2中 製備摻合物2很耗能。但相比摻合物i，其2,2,_MDI含量明顯降 低。 實施例3(對比） 由35.9重量％聚合物級、45 7%粗單體、18 3%2,4,_級製得的 混合MDI產物具有以下產品質量： 級別 2,2'-MDI 2,4'-MDI 4,4'-MDI 雙核MDI總量 MCB PHI 骑物3 0.56% 16.3% 62.5% 79.4% 114ppm 22ppm 10 實施例3顯示摻合物3不能滿足用戶的要求，即溶劑含量小 於20ppm ’ PHI含量小於i〇ppm(摻合物2符合這些）。但是，其 2,2'-MDI低含量和實施例2所得的相當。 實施例4(本發明） 由35.9重量％聚合物級、45.7%純的粗單體、18.3%2,4，-級製 得的混合MDI產物具有以下產品質量： 級別 2,2'-MDI 2,4'-MDI 4,4'-MDI 雙核MDI總量 MCB PHI 0.56% 16.3% 62.5% 79.4% <10ppm <8ppm 20 製備這種掺合物僅需要約18%的高能耗精餾異構體產物，這 意味者精潑異構體產物的用量降低約70%。使用很複雜的方法由 MDA製得的兩種聚合物級Α和Β可以一起省去。製得其質量和 實施例2相當的產物，其中2,2'-MDI含量僅稍微增大。 •17· 實施例5(本發明） 若實際需要2,2’-MDI含量高達3.9重量％，可以使用包含約 50%2,2*-MDI和約50%2,4，-MDI的額外產品質量（富2,2·-型)作為 第四組分。實施例1的起始值可以通過這種方式準確再現。 由30.2%聚合物級、51.8%純的粗單體、11.4%2,4’-級和 6·7%2,2'-級製得的混合MDI產物具有以下產品質量： 級別 2,2'-MDI 2,4'-MDI 4,4'-MDI 雙核MDI總量 MCB PHI 私物5 3.9% 16.3% 62.5% 82.7% <10ppm <8ppm 製備摻合物5僅需要約18%的精餾產物（富2,2'-的級和富2,4'-的級）。所述精心製得的聚合物級Α和Β可以一起省去。這將導 致與實施例1相比，高能耗製得的原料用量降低約80%。 實施例6(對比） 在40°C的授拌釜反應器中混合l〇〇〇g苯胺和3〇6g31.9%鹽酸 水溶液。在15分鐘内逐滴加入480g 32%甲搭溶液。首先，在4〇〇C 下再攪拌15分鐘，並在之後2.5小時内將溫度緩慢升至丨〇〇。〇。 然後’在100°C下將所述反應混合物攪拌回流1〇小時，並用5〇% 氫氧化鈉水溶液中和，將所述水相分離，並用水清洗所述有機 相。除去所述有機溶液，並真空蒸餾除去過量的苯胺。將所述 MDA反應產物倒入第二授拌爸反應器中，所述反應器包含15% 用冰冷卻的光氣的單氯苯(MCB)溶液，光氣摩爾數過量15〇0/〇。在 1小時内’將所述反應溶液缓慢加熱至l〇〇°c，同時連續加入4〇 升/小時的光氣。再在1小時内將所述混合物加熱至沸點，停止加 入光氣並抽真空》將所述溫度逐漸升至21〇°c，壓力降至3毫巴， 並完全除去所述溶劑。製得包含58重量％單體MDI(包含0.21重 1325856 量％2,2’-河01、5.1 重量％2,4，-；\«)1、52.7 重量％4,4，-1^)1)、65ppm MCB和M.5ppmPHI的粗MDI混合物。 將所述粗MDI混合物分離為聚合MDI產物和粗單體餾分(雙 核MDI)。具有向下面底部蒸發器進料的產物的玻璃柱用作實驗 5 裝置’該柱僅包含分滴器填料而不含分離板。所述餾出液在頂部 完全凝結並除去❶所述頂部壓力通過真空泵調至5毫巴。 在180°C下將500g/h粗MDI混合物流供給所述連續操作的設 備°在進料2小時之後，從所述設備排出以下作為產物的物流： 蒸餾設備的底部：10分鐘内62g，具有如下組成， 10 0.09% 2,2'-MDI ' 3.7% 2,4'-MDI ' 39.8%4,4'-MDI > 0.5ppmAlthough the preparation of Blend 2 does not require any elaborately prepared polymer MDA grade A 1325856 r or B ' or phosgenation products (polymers a and b), 64 weight ❶/〇 pure 4,4'- and must be used. Rich 2,4'-grade (made using a very complicated method). Therefore, the preparation of Blend 2 in Example 2 is very energy intensive. However, the 2,2,_MDI content was significantly lower than that of the blend i. Example 3 (Comparative) A mixed MDI product prepared from 35.9 wt% polymer grade, 45 7% crude monomer, 18 3% 2,4, _ grade has the following product qualities: Grade 2, 2'-MDI 2, 4'-MDI 4,4'-MDI Dual core MDI total MCB PHI rider 3 0.56% 16.3% 62.5% 79.4% 114ppm 22ppm 10 Example 3 shows that blend 3 does not meet the user's requirements, ie solvent content is less than 20ppm ' The PHI content is less than i〇ppm (blend 2 meets these). However, its 2,2'-MDI low content is comparable to that obtained in Example 2. Example 4 (Invention) A mixed MDI product prepared from 35.9 wt% polymer grade, 45.7% pure crude monomer, 18.3% 2,4,-grade has the following product qualities: Grade 2, 2'-MDI 2 , 4'-MDI 4,4'-MDI Dual Core MDI Total MCB PHI 0.56% 16.3% 62.5% 79.4% <10 ppm < 8 ppm 20 Preparation of this blend requires only about 18% of high energy distillation and isomerization The body product, which means that the amount of the refined isomer product is reduced by about 70%. Two polymer grades of ruthenium and osmium prepared by MDA using a very complicated method can be omitted. A product of the same quality as in Example 2 was obtained in which the 2,2'-MDI content was only slightly increased. • 17· Example 5 (Invention) If the actual 2, 2'-MDI content is as high as 3.9% by weight, additional products containing about 50% 2,2*-MDI and about 50% 2,4,-MDI can be used. The mass (rich 2,2·-type) is used as the fourth component. The starting value of Embodiment 1 can be accurately reproduced in this way. The mixed MDI product prepared from 30.2% polymer grade, 51.8% pure crude monomer, 11.4% 2,4'-grade and 6.7% 2,2'-grade has the following product qualities: Level 2, 2' -MDI 2,4'-MDI 4,4'-MDI Dual core MDI total MCB PHI Private 5 3.9% 16.3% 62.5% 82.7% <10 ppm < 8 ppm Preparation of Blend 5 requires only about 18% of the rectified product (rich 2, 2'-level and rich 2, 4'-level). The carefully prepared polymer grade ruthenium and osmium can be omitted together. This would result in a reduction in the amount of raw material produced by high energy consumption by about 80% compared to Example 1. Example 6 (Comparative) 10 g of aniline and 3 g of 6 g of a 31.9% aqueous hydrochloric acid solution were mixed in a 40 ° C stirred tank reactor. 480 g of a 32% solution was added dropwise over 15 minutes. First, stir for another 15 minutes at 4 ° C and slowly raise the temperature to 丨〇〇 within 2.5 hours. Hey. Then, the reaction mixture was stirred under reflux at 100 ° C for 1 hour, and neutralized with a 5 % aqueous sodium hydroxide solution, the aqueous phase was separated, and the organic phase was washed with water. The organic solution was removed and excess aniline was removed by vacuum distillation. The MDA reaction product was poured into a second dosing reactor containing 15% ice-cooled phosgene monochlorobenzene (MCB) solution with a molar excess of phosgene of 15 〇0/〇. The reaction solution was slowly heated to 1 °C over 1 hour while continuously adding 4 liters/hour of phosgene. The mixture was again heated to the boiling point within 1 hour, the addition of phosgene was stopped and the vacuum was applied. The temperature was gradually increased to 21 ° C, the pressure was lowered to 3 mbar, and the solvent was completely removed. Manufactured to contain 58% by weight of monomeric MDI (containing 0.21 by weight of 1,325,856% by 2,2'-river 01, 5.1% by weight of 2,4,-;\«) 1, 52.7 wt% 4,4,-1^)1 ), a crude MDI mixture of 65 ppm MCB and M. 5 ppm PHI. The crude MDI mixture is separated into a polymeric MDI product and a crude monomer fraction (dual core MDI). A glass column having the product fed to the lower bottom evaporator was used as the experiment 5 device' This column contained only the separator package without the separation plate. The distillate was completely condensed at the top and removed. The top pressure was adjusted to 5 mbar by a vacuum pump. A 500 g/h crude MDI mixture stream was supplied to the continuously operated apparatus at 180 ° C. After 2 hours of feeding, the following stream as product was discharged from the apparatus: bottom of the distillation apparatus: 62 g in 10 minutes, with Composition as follows, 10 0.09% 2,2'-MDI ' 3.7% 2,4'-MDI ' 39.8%4,4'-MDI > 0.5ppm
MCB、4ppm PHI 其餘部分：聚合MDI(25°C下底部組分粘度：185mPas) 蒸餾設備頂部流體：10分鐘内21g，具有如下組成， 0.57% 2,2’-MDI、9.0% 2,4’-MDI、89.3%4,4，-MDI、241ppmMCB, 4ppm PHI The rest: Polymeric MDI (bottom component viscosity at 25 °C: 185 mPas) Distillation equipment top fluid: 21 g in 10 minutes, with the following composition, 0.57% 2,2'-MDI, 9.0% 2,4' -MDI, 89.3% 4,4,-MDI, 241ppm
15 MCB ' 44ppm PHI 組成中所有的％均以各完整樣品的重量計e 實施例7(本發明）： 將實施例6的粗MDI混合物分離為聚合MDI產物和乾淨的 20 純的粗單體以及低沸點組分。 所用的實驗裝置如下：具有向底部蒸發器進料的產物進料器 以及有4個理論分離步驟的不銹鋼蒸餾填料的玻璃柱，來自該實 驗柱頂部的流體回流可排出回流液部分返回到所述柱中。在頂 部，所述餾出液可以完全凝結，並且使用樣品分離器將其中的95〇/。 25 料回餘返回到所述柱巾^通過真空泵將頂部壓力狀為$毫 巴。 在！8〇C下將5〇〇g/小時粗MDI混合物流供給所述連續操作 1325856 的設備◊進料2個小時後，從設備中排出作為產物的以下物流： 蒸餾設備的底部：10分鐘内60g，具有如下組成，15% of the MCB '44 ppm PHI composition is based on the weight of each intact sample. Example 7 (Invention): The crude MDI mixture of Example 6 is separated into a polymeric MDI product and a clean 20 pure crude monomer and Low boiling point component. The experimental apparatus used was as follows: a product feeder having a feed to the bottom evaporator and a glass column of stainless steel distillation packing having four theoretical separation steps, and a fluid reflux from the top of the experimental column was discharged to return the reflux portion to the In the column. At the top, the distillate can be completely condensed and 95 〇/ of it is used using a sample separator. 25 Return the material to the kerchief ^ The top pressure is $ mbar by a vacuum pump. in! The 5 〇〇g/hr crude MDI mixture stream was supplied to the equipment of the continuous operation 1325856 at 8 〇C for 2 hours, and the following stream as a product was discharged from the equipment: bottom of the distillation apparatus: 60 g in 10 minutes , has the following composition,
0.08% 2J-MDI、3.6% 2,4，-MDI、39.9%4,4··ΜΕ)Ι、〇 5ppm MCB、4ppm PHI 其餘部分：聚合MDI(25°C下底部組分粘度：205mPas) 蒸館設備頂部流體：10分鐘内2g，具有如下組成，0.08% 2J-MDI, 3.6% 2,4,-MDI, 39.9% 4,4··ΜΕ)Ι,〇5ppm MCB, 4ppm PHI Others: Polymerized MDI (bottom component viscosity at 25°C: 205mPas) Steaming The top of the equipment equipment fluid: 2g within 10 minutes, has the following composition,
2·0〇/❶ 2,2，-MDI、17.0% 2,4，-MDI、80.7%4,4，_MDI、73〇ppm MCB ' 380ppm PHI 兩個分離填料元件之間蒸餾設備的側流(對應於純的粗單體2·0〇/❶ 2,2,-MDI, 17.0% 2,4,-MDI, 80.7%4,4,_MDI, 73〇ppm MCB '380ppm PHI Sidestream of the distillation equipment between two separate packing elements ( Corresponding to pure crude monomer
德分）：10 分鐘 19g，組成如下，0.45% 2,2，-MDI、8.7% 2,4,-MDI、 90.7%4,4’_MDI、12ppmMCB、6ppmPHI 組成中所有的％均以各完整樣品的重量計e 上述實施例顯示，和已有技術比較，由本發明方法制 的粗單體製備摻合產物可以提供決定性的優點： •通過用純的粗單體替換摻合物中的聚合物級八和8，可以 顯著降低#合產物中的2,2，-MDI含量，它提高了反應活 性’並降低殘留的單體含量。 •通過用純的粗單體替換摻合物中的粗單體，可以顯著降低 所述摻合產物中的溶劑如MCB、異氰酸苯酯和光氣的含 量。 =雖然以上詳細說明了本發明，但是應理解，這些細節僅用於 說明，在不背離本發明精神和範圍的條件下本領域那些技術人員 可以作出各種變化，除了它為權利要求書所限制。 -20-De points): 19 minutes in 10 minutes, the composition is as follows, 0.45% 2,2,-MDI, 8.7% 2,4,-MDI, 90.7% 4,4'_MDI, 12ppmMCB, 6ppmPHI Weight meter e The above examples show that the preparation of the blended product from the crude monomer produced by the process of the invention provides a decisive advantage over the prior art: • By replacing the polymer grade in the blend with a pure crude monomer Eight and eight can significantly reduce the 2,2,-MDI content of the #co-product, which increases the reactivity' and reduces the residual monomer content. • By replacing the crude monomer in the blend with a pure crude monomer, the solvent such as MCB, phenyl isocyanate and phosgene in the blended product can be significantly reduced. The invention has been described in detail above, but it is to be understood that the details of the invention are to be understood by those skilled in the art without departing from the scope of the invention. -20-